OBJECTIVES: While gene expression tests for breast cancer are widely used in the US, the EU adoption was much delayed due to differences in the reimbursement trajectory. Therefore, it is of interest to understand why in European countries, despite favoring personalized medicine, reimbursement decisions on gene expression testing vary in outcome.

METHODS: A most-similar case comparison between European countries with a positive MammaPrint reimbursement decision (Spain & Greece) and countries with conditional reimbursement (Belgium & France) was conducted. Rational choice institutionalism theory was used to explain differences in outcome.

RESULTS: In all countries, the intrinsic prognostic value of MammaPrint for physicians to assist in chemotherapy decision-making was considered as large, especially in a patient group with an uncertain treatment recommendation. Therefore, following the MINDACT-trial results, all authorities granted reimbursement, but executed it differently. Whereas, Spain & Greece appointed an intended use population for MammaPrint directly following the HTA, Belgium & France are more entangled in the sentiment of uncertainty of what the intended use should be. Belgian and French authorities required the development of a framework that could dictate when gene expression testing should be used. Only after the development of a framework that delineates use to the desired patient population, a full positive reimbursement decision can be established. From a rational choice perspective, the balance in weight put on the broad availability of MammaPrint and the necessity to document physicians usage behavior to identify the intended use population that derives the most benefit appears to influence the policy of choice.

CONCLUSIONS: All included countries acknowledge the value of MammaPrint in medical decision-making, especially when clinicopathological factors are unable to provide sufficient information for a well-considered adjuvant chemotherapy treatment choice. The request of some countries for more data, despite a robust HTA process, results in uncertainties for full patient access.